This paper presents a frequency-domain imaging algorithm for near-field one-stationary bistatic synthetic aperture radar (OS-BiSAR) in the millimeter-wave (mmW) band. During the image reconstruction process, the interpolation procedure introduced by traditional fast imaging algorithm is avoided. By appropriately decomposing and approximating the nonlinear phase in frequency-domain echo, only multiplication and fast Fourier transform operations are carried out to achieve the lowest computational load. In addition, this method takes the propagation attenuation into consideration, which leads to a better imaging quality than the improved range migration algorithm for distant targets. Both simulation and measurement results validate the effectiveness of the proposed method on high-precision real-time imaging.